Automatic vapor-take-off valve for oil tanks



March 15 1927. 1,620,718

Filed Ngv. 13. 1922 /2 1 y f o 20 0 1 0 o H 2, ///=\\\IIIIIIII[live/037;

Patented Mar. 15, 1927.

UNITED STATES 1,620,718 PATENT oer-lies.

CHARLES 1?; BUCK, F TOPEKA,,KANSAS, .ASSIGNOE TO GUSTIN-BACCNMANUFACTUR- INGCOMPANY, OF KANSAS CITY, MISSOURI, A CORPORATION OFMISSOURI.

AUTOMATIC VAPOR-TAKE-OFF VALVE FOR OILWIAZ-NKS.

Application filed November 13,1922. Serial No. 600,759.

The present invention relates to vacuum controlling devicesfor oiltanks, and has for its particular object to devise an improved automaticvalve for controlling the outlet to v the-pump or vapor dischargelinesprovided for drawing 0a the vapor contents fromsuoh tanks.

For. this purpose I have devised an improved valve construction inwhichprovision is made for maintaining the valve in normally open position,but of such a character that the valveisadapted to beautomaticallyclosediin responseto an excessive dnopin the vapor pressure within thevapor space of r the tank. a

With this general object in: view, as well asvariousminor details ofimprovement as will hereinafter appear, the invention will now bedescribed by reference to the accompanying drawing illustrating one formof construction which I have devised for embodyingthe same, after whichthose features deemed to be novel will be particularly set forth andclaimed.

In the drawing- Figure 1 is an elevation illustrating an oil tank(partly broken away) equipped with a valve constructed in accordancewith the present invention;

Figure 2 is a plan view of the valve structureon an enlarged scale;-

Figure 3 is a section taken on the line III-J11 of Figure 2;

Figure 4 is a horizontal section on the-line I-VIV of Figure 31; and

Figure 5 is an enlarged detail sectional view of aportion of a valve andvalve passage.

Referring now to the drawing in detail, this shows the invention in itsrelation to an oiltank7, from the top or deck of which extends avaporintake pipe 8 depending within the vapor space 90f the tank in proximityto the oil level'therein. The valve construction nowto. be describedinvolves certain features of improvement over a valve of similarconstruction as set forth in my copending application Serial No. 485,779iiled July 18,

1921', and comprises a Valve casing 10 having an intake opening 11 forconnection with the upper end of the pipe 8, and an outlet opening 12for connection with the vapor discharge pipe ll; this pipe 14, under theaction'of suitable suction means, as a pump 15, is designed to conductthe vapor from the having at its upper endaseries 0t: laterali ports 17aflording communication; between the oasing-and'the outlet opening 12,and the passage through said; ports is controlled by means of a, hollowvalve or. sleeve 18: which 1 is open at both ends (:see Figure 3) andprovided at its upper end with a bevelledsurface 191 designed forengagement witha bevelled valve seat 201M", the upper end ofthevalvepassage adjacent to the ports 17. At

the lower edge of the surface 19 the valve 18 is formed with; an annularofiset or recessv 21 (seeFigvure 5) designed to provide a clearancespace for any foreign matter. which may be blown off the surface 19asthe valve approaches: the upper limit of its movementfor closing theports 17.

Extending through thevalve sleeve 18 and; pivotally connected to itslower end is a suporting link 22 carrying, inside the valve sleeve, asuitable oounterpoiseelement 23, the weight ofwhich, combined with thatof the valve, is adapted to. maintain the latter normally inloweredpositionv for open ing the ports 17. into communication with theoutlet opening 12. The upper end of said link. 22' is pivoted to thelonger arm of a lever 24 fulcrumed to the casing 10 at 25 and having itsshorter arm pivotally connected. with a lug 26 depending centrally froma disc 27 which in turn is clamped to the undertace of a flexiblediaphragm member 28. The edge of this diaphragm 28 is cover member 30formed with sheltered air oassa 'es 31 to leave the outer or u or face 1a PP of the diaphragm exposed to atmospheric pressure. The interior ofthe cover member and the adjacent portion of the, casing 10 aresoconstructed as to afford proper clearance for the movements of thediaphragm in response to variations in the vapor pressure to which theunderface of the diaphragm is subjected, and toy transmit such movementsthrough the lever 24 to the valve18.

The casing 10 is also'providled with an opening 33 in line with thevalvepassage formed by the partition 16 to permit access to thevalve andvalve seat when necessary, this opening being normally closed by asuitable cap plate 34.

The function of the valve is to automatically close the ports 17whenever the pressure of the vapor within the tank (and hence within thevalve casing) falls below a predetermined point, and thereby protectsthe tank against any excessive vacuum being produced therein. It isobvious that the arrangement of the valve and its connections is such asto maintain the valve normally at the lower end of the valve passage,leaving the ports 17 open so long as the pressure against the lower faceof diaphragm 28 is sufiicient to somewhat more than counterbalance theatmospheric pressure on the outer face of the diaphragm; but as soon asthis vapor pressure drops to a certain point, it is apparent that thediaphragm will be actuated in response to the unbalanced pressure on itsouter face, with the result that the valve will be lifted intoengagement with the seat 20. This engagement of the bevelled surface 19of the valve against the bevelled seat 20 effects a positive closing ofthe valve as against the entry of any vapor or gas between the upper endof the valve and the wall of the valve passage; and the body of thevalve sleeve is of such a length as to effectually oppose, by friction,any passage of the vapor between its outer face and the wall of thevalve passage and prevent such vapor from reaching the ports 17 by wayof the valve passage from the lower end thereof. It will also be evidentthat by permitting the valve to reach its seat, the diaphragm iseffectually reinforced against possible rupture by the development of anexcessive vacuum from any cause within the valve casing, and thediaphragm is also provided against rupture through the development of anexcessive pressure by contact of the arm 24 with the top of thepartition. The described construction provides an efficientpressure-responsive valve-actuating means whereby the slight movement ofa diaphragm is combined with lever and link means to effect a greateramplitude of movement of the valve, and by proper proportioning of theparts the valve movement may be made as sensitive as desired.

The valve andits mechanism are all fully enclosed in compact form, sothat the structure is adapted for use, with any special form of seal ofsuitable type to protect the mechanism against unauthorized tampering.

While I have illustrated and described what is now thought to constitutethe preferred form of construction, I desire to reserve the right tomake such changes or modifications as may fairly fall within the scopeof the appended claims.

What I claim is:

1. In combination wit-h a tank having a vapor discharge pipe, a valvepassage open at both ends to said vapor space and provided at its upperend with lateral ports affording communication between said space anddischarge pipe, said passage being formed with a valve seat adjacent tosaid ports, a hollow valve open at both its ends and lidingly mounted insaid passage and adapted to close said ports when in engagement withsaid valve seat, the body of said valve extending, when in closedposition, to

t a material distance below said ports suificient to seal the latterfrlctionally against vapor entering from the lower end of said passageand around said valve, and means for maintaining said valve normally inopen position while permitting the same to be closed in response to apredetermined reduction in the vapor pressure within said vapor space.

2. In combination with a tank having a vapor discharge pipe, a valvepassage provided at one end with lateral ports affording communicationbetween said pipe and the vapor space within the tank, said passagebeing formed with a valve seat adjacent to said ports, a valve slidinglymounted in said passage and adapted to close said ports when inengagement with said valve seat, said valve being formed with an offsetto provide a clearance space at the lower margin of said valve seat whensaid valve is in closed position, and means for maintaining said valvenormally in open position while permitting the same to be closed inresponse to a predetermined reduction in the vapor pressure within saidvaporspace.

3. In combination with a valve casing having a pair of openings, a valvepassage provided with lateral ports affording communication between oneof said openings and the interior of the casing, said passage also beingformed with an interior valve seat, an open-ended cylindrical valveslidingly mounted in said passage and adapted to close said ports whenin engagement with the valve seat, and a pressure-actuated diaphragmconstantly exposed to the pressure within the casing operativelyconnected to said valve.

4c. In combination with a valve casing having a pair of openings, avalve passage having a port affording eommunlcation between one of saidopenings and the interior of the casing, a valve seat within saidpassage, an open-ended cylindrical valve slidingly mounted in thepassage and adapted to close said port when in abutment with the wilveseat, a lever pivoted intermediate its length to the casing, aconnection at one end of said lever to the valve, and a pressureactuateddiaphragm constantly exposed to the pressure within the casingoperatively connected to the other end of said lever.

5. In combination with a valve casing having a pair of openings, avertical tubular passageway Within said casing having a port pivotallysecured to one end of said lever, affording communication between one ofand a connection secured at one end of said 10 said openings and theinterior of the casing, lever and pivotally mounted at its other end acylindrical valve slidingly mounted in the adjacent the lower end ofsaid cylindrical passage and adapted to close said port, an valve.

open-ended lever pivoted Within the casing, In Witness whereof Ihereunto alfix my a pressure-actuated diaphragm constantly signature.

exposed to the pressure Within the casing CHARLES P. BUCK.

